NGC 2175 is today recognised as a part of SH2-252, an extended H-II region in direction of the galactic anticenter. If we accept NGC 2175's distance to be 7200 light-years, it extends some 84x64 ly in true physical extent, which makes it about twice as big as the Great Orion Nebula.
[from O'Meara]
Date: 01/11/2013
Size:
Image Data
Telescope: RCOS 20" f/8.5
Mount: Paramount ME
Detector: Apogee U16M
Filters: Astrodon Gen 2, 3nm/5nm Narrowband
Exposures: SII:Ha:OIII 360:450:420 min (30min subs)
Observatory: Sierra Remote, California
